Purpose:

This insert fills the empty space inside an AR-15 buffer tube (receiver extension) when the buffer and buffer spring are removed.

Compatibility:

Works with Right To Bear .22LR uppers

Works with CMMG .22LR conversion bolts

May also fit BRN-180 and FM-15 self-contained uppers, but durability will be reduced due to heavier recoil compared to .22LR

Installation Notes:

The insert fits with the buffer retainer detent installed, but removing the detent makes installation and removal easier

Slide the insert into the buffer tube until fully seated

Printing Recommendations:

Use at least 15% infill with a concentric pattern

The design has two pieces; gluing them together makes handling easier, but this is optional and not required for function

LBRY Tags: ar15; fosscad; 3d2a; firearms; 3d printing